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Fair Value Measurements. (Details) - Schedule of fair values of warrants based on unobservable inputs $ in Thousands | 12 Months Ended
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Dec. 31, 2020 USD ($)
Warrants to Senior Noteholders [Member] |
Fair Value Measurements. (Details) - Schedule of fair values of warrants based on unobservable inputs [Line Items] |
Balance, December 31, 2019 | $ 977
Issuance of warrants in October offering |
Exercise of warrants/reclass to equity | (8,474)
Adjustments to fair value for the period | 7,497
Balance, December 31, 2020 |
Pre-funded Warrants [Member] |
Fair Value Measurements. (Details) - Schedule of fair values of warrants based on unobservable inputs [Line Items] |
Balance, December 31, 2019 |
Issuance of warrants in October offering | 23,638
Exercise of warrants/reclass to equity | (21,917)
Adjustments to fair value for the period | (1,721)
Balance, December 31, 2020 |
Other Warrants [Member] |
Fair Value Measurements. (Details) - Schedule of fair values of warrants based on unobservable inputs [Line Items] |
Balance, December 31, 2019 |
Issuance of warrants in October offering | 27,048
Exercise of warrants/reclass to equity | (31,231)
Adjustments to fair value for the period | 4,183
Balance, December 31, 2020 |

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